Amalgam dispenser



1965 c. J. THlEL ETAL 3,221,409

AMALGAM DISPENSER Filed Dec. 12. 1961 United States Patent 3,221,469AMALGAM DISPENSER Charles J. Thiel, 625 6th Ave., and Louis J. Michaels,1210 6th Ave., both of Dayton, Ky. Filed Dec. 12, 1961, Ser. No. 158,6818 Claims. (Cl. 3260) This invention relates to an amalgam dispenser andmore particularly this invention relates to a plunger operated amalgamdispenser by which the amalgam can be discharged through a tube instep-by-step fashion by manipulating a lever pivoted on the dispenser.

In the practice of dentistry, one of the most tedious aspects of fillinga cavity is that operation which consists of the mixing of the amalgamand dispensing and packing the amalgam into a tooth. The mixing ofamalgam preparatory to introduction into a tooth has been greatlysimplified by the apparatus disclosed in our co-pending applicationSerial No. 145,878 filed October 18, 1961. That application is directedto apparatus for mixing amalgam and, in the preferred embodiment of thatapplication, the amalgam is dispensed from the mixing chamber into anelongated tube. The tube is adapted to be removed from the mixingapparatus and snapped either onto the end of a dispenser or in thebreech of a dispenser for subsequent ejection through the manipulationof a plunger projection from the rear of the dispenser. Discharging ofamalgam from the dispenser disclosed in that application is a somewhatawkward process in view of the necessity of pushing the plunger from therear of the instrument while at the same time guiding the dischargingamalgam into the tooth of the patient.

The present invention is directed to an improvement in the dispensershown in our co-pending application. It has been an objective of thepresent invention to provide a dispenser having a lever extendinggenerally parallel to the dispenser the lever being connected to theplunger passing through the dispensing tube in such a manner as to drivethe plunger in a forward direction when the lever is depressed.Preferably the lever is positioned on the dispenser so that it can beconveniently manipulated by the dentist as he holds the dispenser in onehand while directing the dispensing tube into the mouth of the patientadjacent the cavity to be filled.

It has been another objective of the invention to provide a dispenserhaving a lever operated plunger in which the cooperative engagement ofthe lever to the plunger is in the form of a ratchet and pawl. With theratchet and pawl mechanism it is possible to provide for thestep-by-step dispensing of the amalgam through repeatedly depressing andreleasing the lever. Also through the use of the ratchet and pawlmechanism, the dentist can be assured of dispensing only a predeterminedquantity of amalgam with each manipulation of the lever and therebyobviate the necessity of regulating the exact distance through which thelever is depressed.

It has been still another objective of the invention to provide adispenser having a ratchet and pawl actuated plunger in which amechanism is provided for pre-selecting a one or two or even more toothtraverse of the pawl with respect to the ratchet. This mechanism permitsthe dentist to pre-select for himself the quantity of amalgam which willbe discharged with each depression of the lever. A two tooth traverse ofthe pawl with respect to the ratchet will effect the dispensing of twiceas much amalgam as a one tooth traverse of the pawl with respect to theratchet.

Another objective of the invention has been to provide an amalgam packeron the dispensing tube at the discharge end of the dispenser. Throughthe provision of the combination of a tube through which amalgam isdischarged and a packer, it is possible to dispense a pre- 3,221,409Patented Dec. 7, 1965 ice selected quantity of amalgam and, withoutremoving the dispenser from the mouth of the patient slight rotation ofthe dispenser will bring the packer into position to pack the amalgam inthe patients tooth.

These and other objectives of the invention will become more readilyapparent from the following detailed description taken in conjunctionwith the accompanying drawings in which:

FIG. 1 is a side elevational view of a dispenser in accordance with thepresent invention,

FIG. 2 is a cross sectional view thereof,

FIG. 3 is a cross sectional view taken along lines 33 of FIG. 2,

FIG. 4 is a disassembled view of the connection of the discharge tube tothe dispenser,

FIG. 5 is a disassembled view of an alternative connector,

FIG. 6 is a fragmentary view, partly in section, showing the applicationof the invention to a breech loading dispenser,

FIG. 7 is a fragmentary side elevational view of a discharge tube withan integrally mounted packer,

FIG. 8 is a bottom plan view of the device of FIG. 7, and

FIG. 9 is a fragmentary sectional view of a discharge tube showing theflexible plunger extending to the end of the tube.

Referring to the drawings the dispenser indicated at 10 has a tubularbody portion 11 into which a plunger 12 is slidably mounted. The plungerhas a discharge section 13 which is a flexible nylon rod in thepreferred embodiment, a ratchet section 14 and a handle section 15. Thehandle section 15 has a retracting knob 17 at the end thereof.

The ratchet section is of a diameter just slightly less than the insidediameter of the tubular body portion 11 so that it can slide freelywithout rattling in the dispenser. A friction drag ring 18 is mounted inan annular groove 19 in the ratchet section to provide the frictionalforce between the ratchet section and the body portion 11 which isnecessary to assure proper operation and to avoid inadvertent operation.

The ratchet section 14 has a longitudinal groove or keyway 21 in thebottom thereof which cooperates with a key 22 to prevent rotation of theratchet section with respect to the body portion 11 of the dispenser. Onthe side of the ratchet section opposite the groove 21 is a set ofratchet teeth 23 which are accessable through a slot 24 formed in thebody portion 11 of the dispenser. The ratchet teeth are engageable by apawl 25 which is in the form of a leaf spring. The leaf spring pawl 25is fixed intermediate its ends to an operating lever 26 which is pivotedat 27 to a bracket 28 on the body portion 11.

The operating lever 26 has an elogated lever arm 31 which lies close tothe body portion 11 of the dispenser but is spaced away a distancesufficient for it to be moved toward the body portion in order toactuate the dispenser. The tip portion 32 of the arm 31 is knurled forconvenient engagement by the thumb or fingers of the dentist.

The pawl 25 has a forward end 33 which is engageable with the ratchetteeth. The ratchet teeth are inclined in such a direction as to permitthe forward portion 33 of the pawl to ride over them when the lever 26is released, and to drive the ratchet section in a forward directionwhen the operating lever 26 is depressed. The pawl 25 also has arearward end portion 35 which bears against the body portion 11 as shownin FIG. 2 or bears against a step-up sleeve 36 as shown in FIG. 1. Thestep up sleeve 36 is slidably mounted on the body portion and can bemoved into or out of operative engagement with the rearward end portion35 of the leaf spring pawl in order to change the stroke of theoperating lever. In the operable or engaged position of FIG. 1, thestroke of the operating lever is shortened to a one tooth stroke, thatis a stroke which permits the forward portion 33 of the pawl to traverseonly one ratchet tooth with each operation of the operating lever. Whenthe sleeve 36 is withdrawn as shown in FIG. 2, the operating lever has alarger stroke which permits the traversal of two of the ratchet teethwith a consequent discharge of twice as much amalgam with each stroke.

The bearing of the leaf spring pawl at the forward end against theratchet section and at the rearward end against the body portion 11provides a spring biasing of the operating lever toward the positionshown in FIGS. 1 or 2 and assures the return of the operating lever tothat position at the endof each stroke.

The plunger is confined within the tubular body portion 11 at therearward end thereof by a stop cap 38. At the forward end, the ratchetsection is confined within the body portion 11 by an annular depression39 which may be spun into the tip of the body portion.

The depression 39 provides an annular groove 40 which receives a lip 41on the end of the discharge tube fitting 42. The discharge tube 43 hasbeen described in detail in our co-pending application Serial No.145,878 the disclosure should be considered to be incorporated herein byreference.

A locking sleeve 44 slidably mounted on the body portion 11 and isadapted to be slid over the flexible fitting 42 to provide assuranceagainst the inadvertent detachment of the discharge tube 43 from thedispenser.

It is also desirable to provide assurance against rotation of thedischarge tube with respect to the dispenser. Referring to FIG. 4 aswell as FIG. 2, a pin 45 projects radially from the tip 46 of the bodyportion 11 at approximately the location of the annular groove '40. Theflexible fitting 42 which is slotted as at 47 for proper flexing has arecess 48 which is engageable with the pin 45. When the fitting 42 isproperly seated on the tip '46 as shown in FIG. 2, the recess 48 on thetip is brought into engagement with the pin 45. The subsequent slidingof sleeve 44 over the fitting clamps the fitting against axial removaland maintains the engagement of the recess '48 with the pin 45 thuspreventing inadvertent rotation of the discharge tube 43 with respect tothe dispenser.

An alternative form of means for connecting the discharge tube to thedispenser is illustrated in FIG. 5. In FIG. 5, the rearward end of thedischarge tube indicated at 50 has a rim 51. The tube 50 and the rim 51are receivable in a split locking end 52 of the body portion 11. Theends of the split locking end 52 are grooved as at 53 in order toreceive the rim 51. A locking sleeve 54 is slidable over the splitlocking end 52 to clamp the tip 50 within the split locking end 52.

In FIG. 6 a fragment of a breech loading dispenser is illustrated.There, a body portion 60 of a dispenser has a cavity 61 to receive aloaded tube 62 in a manner similar to that described in connection withour co-pending application Serial No. 145,878. A nylon plunger 63 isslidable through the tube or cartridge 62 in order to expel amalgam fromthe cartridge through the tip 64 and out through a discharge tube whichmay be of any suitable configuration as for example, as shown in FIGS. 1and 2. The plunger 63 is actuated by the mechanism illustrated in FIGS.1 and 2.

The present invention is ideally adapted for a combined-dispenser andpacker. Such a contruction is illustrated in FIGS. 7 and 8. There thedischarge tube indicated at 70 has a packer 71 secured integrallytherewith and angulated with respect to the discharge end 72 of thedischarge tube. The angulation of the packer with respect to thedischarge tube assures that the packer will be out of the way of thetooth when it is being filled by discharge of amalgam through thedischarge end 72, but by mere rotation of thedispenser through a smallangle,

the packer 71 can be brought into position for tamping or packing thatamalgam which has just been discharged into the tube.

OPERATION Preparatory to filling a patients tooth, the amalgam is mixedpreferably in the apparatus illustrated in our copending applicationSerial No. 145,878. At the conclusion of the mixing cycle the amalgam isdischraged into a tube which may be either a tube of the typeillustrated at 43 in FIGS. 1 and 2 or a tube such as is illustrated at62 in FIG. 6. Assuming for the purposes of this description that thetube is similar to tube 43, that tube is removed from the mixingapparatus and secured to the dispenser 10.

Prior to applying the discharge tube to the dispenser the plunger iswithdrawn into the dispenser by pulling handle section 15 all of the wayout by grasping the knob 17 while holding pawl portion 33 out of the wayof the ratchet teeth. The tube is secured to the dispenser merely byslipping it over the forward end thereof and sliding the locking sleeve44 over the fitting 42 as described above.

When the discharge tube with a load of amalgam has been applied to thedispenser, the dispenser is ready for operation. Now at this point thedentist may wish to make a decision as to the quantity of amalgam hewishes to have discharged with each operation of the lever 31. If he isfilling a large cavity, he probably will want to discharge more amalgamthan he would in the filling of a very small cavity. By positioning thesleeve 36 as shown in FIG. 2, approximately twice the amount of amalgamcan be discharged with each stroke of the operating lever 31 as comparedto the setting of the sleeve in FIG. 1.

Assuming that the sleeve 36 has been set as shown in FIG. 2, the dentistbrings the dispenser in the patients mouth and when the end of thedischarge tube 43 is positioned adjacent the cavity to be filled, thelever 31 is depressed. The depressing of the lever 31 swings the pawl 25in a counterclockwise direction which results in the forward end portion33 of the pawl sliding in a forward direction a distance equal to thepitch of two r-atchet teeth. This will effect the discharge of apre-selected quantity of amalgam. Release of the lever 31 permits theleaf spring pawl to return the operating lever 31 to its normal positionas shown in FIG. 2. During the re.- turn of the lever arm to itsposition of rest, the end portion 33 of the pawl traverses two ratchetteeth and lodges in a position ready to drive the plunger forward duringthe next stroke of the operating lever.

If the discharge tube shown in FIGS. 7 and 8 is employed, the dentist isnot even required to set the dispenser down and pick up a packingimplement, rather, he needs to rotate the dispenser slightly in order tobring the packer 71 into position and then proceed to pack the amalgaminto the cavity. The series of operations of dispensing and packing canbe repeated until the tooth has been filled.

After the dispensing operation has been completed and all of the amalgamhas been expelled from the discharge tube 43 by advancing said plungerto the end of a tube as shown in FIG. 9, the plunger should bewithdrawn. This is effected by lifting the forward portion 33 of theratchet pawl 25 out of the way of the ratchet teeth 23 and pulling backon the knob 17. The lifting of the end portion 33 is accomplished byswinging the operating arm 31 slightly in a clockwise direction.

While provision has been made, as illustrated in the drawings, forselectivity between a two tooth dispensing operation and a one toothdispensing operation, it should be well understoodthat through minormodification of the cooperating pawl 25 and sleeve 36, settings can bemade for the pawl to traverse even 3 or 4 teeth during thedispensing. Itshould also be understood that the complete tube 43 can be discharged bydriving the plunger forward through the operation of the knob 17.

We claim:

1. An amalgam dispenser comprising,

an elongated tubular holder having a fitting at its forward end,

an amalgam supply tube having a fitting at one end thereof by which itis attached to the fitting of said holder, the remaining portion of saidtube being of substantially uniform internal diameter throughout itslength,

said tube adapted to be pre-loaded with amalgam and constituting thesole source of supply of amalgam to be dispensed,

a plunger slidably mounted in said holder, said plunger having a forwardend portion terminating adjacent the rear end of said tube when saidtube plunger is rearwardly withdrawn,

said forward end portion being adapted to pass through said tube to itsend to force the amalgam out of said tube,

a plurality of longitudinally spaced ratchet teeth on said plunger,

a pawl having a longitudinally movable portion engaging said teeth,

a lever pivoted on said holder and cooperating with said pawl to movesaid pawl forwardly and rearwardly to move said plunger in a forwarddirection step-by-step.

2. An amalgam dispenser comprising,

an elongated tubular holder having a fitting at its forward end,

an amalgam supply tube having a fitting at one end thereof by which itis attached to the fitting of said holder, the remaining portion of saidtube being of substantially uniform internal diameter throughout itslength,

said tube adapted to be pre-loaded with amalgam and constituting thesole source of supply of amalgam to be dispensed,

a plunger slidably mounted in said holder,

said plunger having a forward end portion terminating adjacent the rearend of said tube when said tube plunger is rearwardly withdrawn,

said forward end portion being adapted to pass through said tube to itsend to force the amalgam out of said tube,

a plurality of longitudinally spaced ratchet teeth on said plunger,

a pawl having a longitudinally movable portion engaging said teeth,

a lever pivoted on said holder and cooperating with said pawl to movethe movable portion of said pawl forwardly and rearwardly to move saidplunger in a forward direction step-by-step,

and a projecting handle on the rearward end of said plunger forreturning said plunger to its rearward position after completion of thedispensing operation.

3. An amalgam dispenser comprising,

an elongated tubular holder having a fitting at its forward end,

an amalgam supply tube having a fitting at one end thereof by which itis attached to the fitting of said holder, the remaining portion of saidtube being of substantially uniform internal diameter throughout itslength,

said tube adapted to be pre-loaded with amalgam and constituting thesole source of supply of amalgam to be dispensed,

a plunger slidably mounted in said holder,

said plunger having a forward end portion terminating adjacent the rearend of said tube when said tube plunger is rearwardly withdrawn,

said forward end portion being adapted to pass through said tube to itsend to force the amalgam out of said tube,

a plurality of longitudinally spaced ratchet teeth on said plunger,

a pawl having a longitudinally movable portion engaging said teeth,

a lever pivoted on said holder and cooperating with said pawl to movethe movable portion of said pawl forwardly and rearwardly to move saidplunger in a forward direction step-by-step,

and means for selectively varying the number of ratchet teeth traversedby said pawl with each operation of said lever.

4. An amalgam dispenser comprising,

an elongated tubular holder having a fitting at its forward end,

a curved amalgam supply tube having a fitting at one end thereof bywhich it is attached to the fitting of said holder, the remainingportion of said tube being of substantially uniform internal diameterthroughout its length,

said tube adapted to be pre-loaded with amalgam and constituting thesole source of supply of amalgam to be dispensed,

an elongated flexible plunger slidably mounted in said holder,

said plunger having a forward end portion terminating adjacent the rearend of said tube when said plunger is rearwardly withdrawn,

said forward end portion being adapted to pass through said tube to itsend to force the amalgam out of said tube,

a plurality of longitudinally spaced ratchet teeth on said plunger,

a pawl having a longitudinally movable portion engagin said teeth,

a lever pivoted on said holder and cooperating with said pawl to movethe forward portion of said pawl forwardly and rearwardly to move saidplunger in a forward direction step-by-step.

5. An amalgam dispenser comprising,

an elongated tubular holder having a fitting at its for- Ward end,

an amalgam supply tube having a fitting at one end thereof by which itis attached to the fitting of said holder, the remaining portion of saidtube being of substantially uniform internal diameter throughout itslength,

said tube adapted to be pre-loaded with amalgam and constituting thesole source of supply of amalgam to be dispensed,

a plunger slidably mounted in said holder,

said plunger having a forward end portion terminating adjacent the rearend of said tube when said tube plunger is rearwardly Withdrawn,

said forward end portion being adapted to pass through said tube to itsend to force the amalgam out of said tube,

a plurality of longitudinally spaced ratchet teeth on said plunger,

an operating lever pivoted on said holder, said lever having a forwardlyprojecting arm lying close to and generally parallel to said holder,

and a pawl mounted on said lever and having a portion engaging saidteeth,

said pawl being movable forwardly and rearwardly upon depressing andreleasing said lever arm to expel amalgam step-by-step.

6. An amalgam dispenser comprising, an elongated tubular holder, aplunger slidably mounted in said holder, said plunger being adapted, atthe forward end thereof to pass through a tube containing amalgam toforce the amalgam out of said tube, a plurality of longitudinally spacedratchet teeth on said plunger, an operating lever pivoted on saidholder, a leaf spring pawl mounted on said lever and having a forwardend engaging said teeth and a rearward end engaging said holder, saidpawl resiliently holding said lever in normal released position, saidpawl being movable forwardly and'rearwardly upon depressing andreleasing said lever to expel amalgam stepby-step, and adjustable ringselectively slidable under the rearward end of said pawl for varying theangle of movement of said lever to vary the stroke of said pawl.

7. An amalgam dispenser comprising, an elongated tubular holder, anamalgam supply tube removably mounted at the forward end of said holder,a plunger slidably mounted in said holder, said plunger having a forwardend portion terminating adjacent the rear end of said tube when saidtube plunger is rearwardly withdrawn, said forward end portion beingadapted to pass through a tube containing amalgam to force the amalgamout of said tube, a plurality of longitudinally spaced ratchet teeth onsaid plunger, an operating lever pivoted on said holder, a leaf springpawl mounted on said lever and having a portion engaging said teeth,said leaf spring pawl resiliently biasing said operating lever to areleased position.

8. An amalgam dispenser and packer comprising,

an elongated holder,

an amalgam supply tube having a curved discharge end, said supply tubebeing removably mounted on said holder,

a packer fixed on said tube and having a free end adjacent saiddischarge end and projecting forwardly at an angle away from saiddischarge end, said packer being adapted to tamp amalgam into a tooth,

a plunger slidably mounted in said holder,

said plunger having a forward end portion terminating adjacent the rearendof said tube when said tube plunger is rearwardly withdrawn,

said forward end portion being adapted to pass through said tubecontaining amalgam to force the amalgam out of said tube,

a plurality of longitudinally spaced ratched teeth on said plunger,

a pawl having a longitudinally movable portion engaging said teeth,

and a lever pivoted on said holder and having its free end extendingtoward said tube and operable to move the movable portion of said pawlforwardly and rearwardly to move said plunger in a forward directionstep-by-step.

References Cited by the Examiner UNITED STATES PATENTS 1,871,399 8/1932Adams 222391 X 1,977,532 10/1934 Taylor et al. 222391 X 1,997,129 4/1935Taylor et a1. 74--169 2,476,793, 7/1949 Arena 3260 2,573,547 10/1951Crowell 32-60 2,598,624 5/1952 Van Der Woude 3260 2,917,830 12/1959Cervens 3260 FOREIGN PATENTS 326,816 2/1920 Germany.

LOUIS J. DEMBO, Primary Examiner.

1. AN AMALGAM DISPENSER COMPRISING, AN ELONGATED TUBULAR HOLDER HAVING AFITTING AT ITS FORWARD END, AN AMALGAM SUPPLY TUBE HAVING A FITTING ATONE END THEREOF BY WHICH IT IS ATTACHED TO THE FITTING OF SAID HOLDER,THE REMAINING PORTION OF SAID TUBE BEING OF SUBSTANTIALLY UNIFORMINTERNAL DIAMETER THROUGHOUT ITS LENGTH, SAID TUBE ADAPTED TO BEPRE-LOADED WITH AMALGAM AND CONSTITUTING THE SOLE SOURCE OF SUPPLY OFAMALGAM TO BE DISPENSED, A PLUNGER SLIDABLY MOUNTED IN SAID HOLDER, SAIDPLUNGER HAVING A FORWARD END PORTION TERMINATING ADJACENT THE REAR ENDOF SAID TUBE WHEN SAID TUBE PLUNGER IS REARWARDLY WITHDRAWN, SAIDFORWARD END PORTION BEING ADAPTED TO PASS THROUGH SAID TUBE TO ITS ENDTO FORCE THE AMALGAM OUT OF SAID TUBE, A PLURALITY OF LONGITUDINALLYSPACED RATCHET TEETH ON SAID PLUNGER, A PAWL HAVING A LONGITUDINALLYMOVABLE PORTION ENGAGING SAID TEETH, A LEVER PIVOTED ON SAID HOLDER ANDCOOPERATING WITH SAID PAWL TO MOVE SAID PAWL FORWARDLY AND REARWARDLY TOMOVE SAID PLUNGER IN A FORWARD DIRECTION STEP-BY-STEP.